"""Support for KNX sensor entities."""

from __future__ import annotations

from collections.abc import Callable
from dataclasses import dataclass
from datetime import datetime, timedelta
from functools import partial
from typing import Any

from xknx.core.connection_state import XknxConnectionState, XknxConnectionType
from xknx.devices import Device as XknxDevice, Sensor as XknxSensor

from homeassistant import config_entries
from homeassistant.components.sensor import (
    CONF_STATE_CLASS,
    RestoreSensor,
    SensorDeviceClass,
    SensorEntity,
    SensorEntityDescription,
    SensorStateClass,
)
from homeassistant.const import (
    CONF_DEVICE_CLASS,
    CONF_ENTITY_CATEGORY,
    CONF_NAME,
    CONF_TYPE,
    CONF_UNIT_OF_MEASUREMENT,
    STATE_UNAVAILABLE,
    STATE_UNKNOWN,
    EntityCategory,
    Platform,
)
from homeassistant.core import HomeAssistant
from homeassistant.helpers.entity_platform import (
    AddConfigEntryEntitiesCallback,
    async_get_current_platform,
)
from homeassistant.helpers.typing import ConfigType, StateType
from homeassistant.util.enum import try_parse_enum

from .const import ATTR_SOURCE, CONF_SYNC_STATE, DOMAIN, KNX_MODULE_KEY
from .dpt import get_supported_dpts
from .entity import (
    KnxUiEntity,
    KnxUiEntityPlatformController,
    KnxYamlEntity,
    _KnxEntityBase,
)
from .knx_module import KNXModule
from .schema import SensorSchema
from .storage.const import CONF_ALWAYS_CALLBACK, CONF_ENTITY, CONF_GA_SENSOR
from .storage.util import ConfigExtractor

SCAN_INTERVAL = timedelta(seconds=10)


@dataclass(frozen=True)
class KNXSystemEntityDescription(SensorEntityDescription):
    """Class describing KNX system sensor entities."""

    always_available: bool = True
    entity_category: EntityCategory = EntityCategory.DIAGNOSTIC
    has_entity_name: bool = True
    should_poll: bool = True
    value_fn: Callable[[KNXModule], StateType | datetime] = lambda knx: None


SYSTEM_ENTITY_DESCRIPTIONS = (
    KNXSystemEntityDescription(
        key="individual_address",
        always_available=False,
        should_poll=False,
        value_fn=lambda knx: str(knx.xknx.current_address),
    ),
    KNXSystemEntityDescription(
        key="connected_since",
        always_available=False,
        device_class=SensorDeviceClass.TIMESTAMP,
        should_poll=False,
        value_fn=lambda knx: knx.xknx.connection_manager.connected_since,
    ),
    KNXSystemEntityDescription(
        key="connection_type",
        always_available=False,
        device_class=SensorDeviceClass.ENUM,
        options=[opt.value for opt in XknxConnectionType],
        should_poll=False,
        value_fn=lambda knx: knx.xknx.connection_manager.connection_type.value,
    ),
    KNXSystemEntityDescription(
        key="telegrams_incoming",
        entity_registry_enabled_default=False,
        force_update=True,
        state_class=SensorStateClass.TOTAL_INCREASING,
        value_fn=lambda knx: knx.xknx.connection_manager.cemi_count_incoming,
    ),
    KNXSystemEntityDescription(
        key="telegrams_incoming_error",
        state_class=SensorStateClass.TOTAL_INCREASING,
        value_fn=lambda knx: knx.xknx.connection_manager.cemi_count_incoming_error,
    ),
    KNXSystemEntityDescription(
        key="telegrams_outgoing",
        entity_registry_enabled_default=False,
        force_update=True,
        state_class=SensorStateClass.TOTAL_INCREASING,
        value_fn=lambda knx: knx.xknx.connection_manager.cemi_count_outgoing,
    ),
    KNXSystemEntityDescription(
        key="telegrams_outgoing_error",
        state_class=SensorStateClass.TOTAL_INCREASING,
        value_fn=lambda knx: knx.xknx.connection_manager.cemi_count_outgoing_error,
    ),
    KNXSystemEntityDescription(
        key="telegram_count",
        force_update=True,
        state_class=SensorStateClass.TOTAL_INCREASING,
        value_fn=lambda knx: knx.xknx.connection_manager.cemi_count_outgoing
        + knx.xknx.connection_manager.cemi_count_incoming
        + knx.xknx.connection_manager.cemi_count_incoming_error,
    ),
    KNXSystemEntityDescription(
        key="telegrams_data_secure_undecodable",
        entity_registry_enabled_default=False,
        state_class=SensorStateClass.TOTAL_INCREASING,
        value_fn=lambda knx: knx.xknx.connection_manager.undecoded_data_secure,
    ),
)


async def async_setup_entry(
    hass: HomeAssistant,
    config_entry: config_entries.ConfigEntry,
    async_add_entities: AddConfigEntryEntitiesCallback,
) -> None:
    """Set up entities for KNX platform."""
    knx_module = hass.data[KNX_MODULE_KEY]
    platform = async_get_current_platform()
    knx_module.config_store.add_platform(
        platform=Platform.SENSOR,
        controller=KnxUiEntityPlatformController(
            knx_module=knx_module,
            entity_platform=platform,
            entity_class=KnxUiSensor,
        ),
    )

    entities: list[SensorEntity] = []
    entities.extend(
        KNXSystemSensor(knx_module, description)
        for description in SYSTEM_ENTITY_DESCRIPTIONS
    )
    if yaml_platform_config := knx_module.config_yaml.get(Platform.SENSOR):
        entities.extend(
            KnxYamlSensor(knx_module, entity_config)
            for entity_config in yaml_platform_config
        )
    if ui_config := knx_module.config_store.data["entities"].get(Platform.SENSOR):
        entities.extend(
            KnxUiSensor(knx_module, unique_id, config)
            for unique_id, config in ui_config.items()
        )
    async_add_entities(entities)


class _KnxSensor(RestoreSensor, _KnxEntityBase):
    """Representation of a KNX sensor."""

    _device: XknxSensor

    async def async_added_to_hass(self) -> None:
        """Restore last state."""
        if (
            (last_state := await self.async_get_last_state())
            and last_state.state not in (STATE_UNKNOWN, STATE_UNAVAILABLE)
            and (
                (last_sensor_data := await self.async_get_last_sensor_data())
                is not None
            )
        ):
            self._attr_native_value = last_sensor_data.native_value
            self._attr_extra_state_attributes.update(last_state.attributes)
        await super().async_added_to_hass()

    def after_update_callback(self, device: XknxDevice) -> None:
        """Call after device was updated."""
        self._attr_native_value = self._device.resolve_state()
        if telegram := self._device.last_telegram:
            self._attr_extra_state_attributes[ATTR_SOURCE] = str(
                telegram.source_address
            )
        super().after_update_callback(device)


class KnxYamlSensor(_KnxSensor, KnxYamlEntity):
    """Representation of a KNX sensor configured from YAML."""

    _device: XknxSensor

    def __init__(self, knx_module: KNXModule, config: ConfigType) -> None:
        """Initialize of a KNX sensor."""
        super().__init__(
            knx_module=knx_module,
            device=XknxSensor(
                knx_module.xknx,
                name=config[CONF_NAME],
                group_address_state=config[SensorSchema.CONF_STATE_ADDRESS],
                sync_state=config[CONF_SYNC_STATE],
                always_callback=True,
                value_type=config[CONF_TYPE],
            ),
        )
        dpt_string = self._device.sensor_value.dpt_class.dpt_number_str()
        dpt_info = get_supported_dpts()[dpt_string]

        if device_class := config.get(CONF_DEVICE_CLASS):
            self._attr_device_class = device_class
        else:
            self._attr_device_class = dpt_info["sensor_device_class"]

        self._attr_state_class = (
            config.get(CONF_STATE_CLASS) or dpt_info["sensor_state_class"]
        )

        self._attr_native_unit_of_measurement = dpt_info["unit"]
        self._attr_force_update = config[SensorSchema.CONF_ALWAYS_CALLBACK]
        self._attr_entity_category = config.get(CONF_ENTITY_CATEGORY)
        self._attr_unique_id = str(self._device.sensor_value.group_address_state)
        self._attr_extra_state_attributes = {}


class KnxUiSensor(_KnxSensor, KnxUiEntity):
    """Representation of a KNX sensor configured from the UI."""

    _device: XknxSensor

    def __init__(
        self, knx_module: KNXModule, unique_id: str, config: dict[str, Any]
    ) -> None:
        """Initialize KNX sensor."""
        super().__init__(
            knx_module=knx_module,
            unique_id=unique_id,
            entity_config=config[CONF_ENTITY],
        )
        knx_conf = ConfigExtractor(config[DOMAIN])
        dpt_string = knx_conf.get_dpt(CONF_GA_SENSOR)
        assert dpt_string is not None  # required for sensor
        dpt_info = get_supported_dpts()[dpt_string]

        self._device = XknxSensor(
            knx_module.xknx,
            name=config[CONF_ENTITY][CONF_NAME],
            group_address_state=knx_conf.get_state_and_passive(CONF_GA_SENSOR),
            sync_state=knx_conf.get(CONF_SYNC_STATE),
            always_callback=True,
            value_type=dpt_string,
        )

        if device_class_override := knx_conf.get(CONF_DEVICE_CLASS):
            self._attr_device_class = try_parse_enum(
                SensorDeviceClass, device_class_override
            )
        else:
            self._attr_device_class = dpt_info["sensor_device_class"]

        if state_class_override := knx_conf.get(CONF_STATE_CLASS):
            self._attr_state_class = try_parse_enum(
                SensorStateClass, state_class_override
            )
        else:
            self._attr_state_class = dpt_info["sensor_state_class"]

        self._attr_native_unit_of_measurement = (
            knx_conf.get(CONF_UNIT_OF_MEASUREMENT) or dpt_info["unit"]
        )

        self._attr_force_update = knx_conf.get(CONF_ALWAYS_CALLBACK, default=False)
        self._attr_extra_state_attributes = {}


class KNXSystemSensor(SensorEntity):
    """Representation of a KNX system sensor."""

    _attr_has_entity_name = True

    def __init__(
        self,
        knx: KNXModule,
        description: KNXSystemEntityDescription,
    ) -> None:
        """Initialize of a KNX system sensor."""
        self.entity_description: KNXSystemEntityDescription = description
        self.knx = knx

        self._attr_device_info = knx.interface_device.device_info
        self._attr_should_poll = description.should_poll
        self._attr_translation_key = description.key
        self._attr_unique_id = f"_{knx.entry.entry_id}_{description.key}"

    @property
    def native_value(self) -> StateType | datetime:
        """Return the state of the sensor."""
        return self.entity_description.value_fn(self.knx)

    @property
    def available(self) -> bool:
        """Return True if entity is available."""
        if self.entity_description.always_available:
            return True
        return self.knx.xknx.connection_manager.state is XknxConnectionState.CONNECTED

    def after_update_callback(self, device: XknxConnectionState) -> None:
        """Call after device was updated."""
        self.async_write_ha_state()

    async def async_added_to_hass(self) -> None:
        """Store register state change callback."""
        self.knx.xknx.connection_manager.register_connection_state_changed_cb(
            self.after_update_callback
        )
        self.async_on_remove(
            partial(
                self.knx.xknx.connection_manager.unregister_connection_state_changed_cb,
                self.after_update_callback,
            )
        )